蒙药那仁满都拉多糖的分离纯化及抗氧化活性研究

目的:从蒙药那仁满都拉中分离多糖,进行定性分析并研究其抗氧化活性。方法: 采用水提醇沉法提取多糖,Sevag法脱蛋白、H₂O₂脱色、透析、再通过DEAE-Cellulose、Sephdex G-100柱色谱进一步纯化,通过比色法测定多糖对氧自由基的清除及对脂质过氧化物(LPO)的抑制作用。结果: 蒙成药那仁满都拉粗多糖的含量为61.9%,纯化后多糖的含量为91.7%。多糖对·OH的清除能力弱于苯甲酸,但强于维生素C和甘露醇;对·O₂^-的清除能力弱于苯甲酸和维生素C,强于甘露醇。当多糖浓度达到一定时可有效降低LPO的终产物——丙二醛(MDA)的含量。结论: 该蒙药多糖对·OH和·O₂^-具有较强的清除作用,其活性大小与浓度呈正效应;对脂质过氧化物具有一定的抑制作用。

Objective: To study the isolation and qualitative analysis and antioxidant activity of polysaccharides from Mongolian medicine Narenmandula. Methods: Polysaccharides were extracted by water extraction and alcohol precipitation,then processed by deproteinization with Sevag method,decolorization with H₂O₂,and dialysis,then were further purified by through DEAE-Cellulose and SephdexG-100 column chromatography.The scavenging effect on oxygen free radicals and inhibition of lipid peroxidation (LPO) of polysaccharides were analyzed by the colorimetric method. Results: The content of crude polysaccharides was 61.9%,and the content of purified polysaccharides was 91.7% in Mongolian medicine Narenmandula,respectively.The scavenging effect of polysaccharides on ·OH was weaker than that of benzoic acid,but stronger than that of Vc and mannitol,and polysaccharides had a weaker scavenging effect on ·O₂^- than benzoic acid and Vc,but stronger than mannitol.When the polysaccharide concentration reached a certain level,it could effectively reduce the content of malondialdehyde (MDA),the final product of LPO. Conclusion: The polysaccharide of Mongolian medicine has a strong scavenging effect on ·OH and ·O₂^-,whose activity is positively correlated with concentration;and it can inhibit lipid peroxidation at certain degree.